The present invention relates to an optical fiber array in which optical fibers are inserted and arranged in V-shaped grooves.
Due to the increasing density of optical fibers, more and more fibers are used for planar waveguides (PLC). To avoid the increase in size of waveguide elements associated with the increasing number of fibers and to further increase the density, efforts are being made to reduce the conventional standard type waveguide pitch.
FIG. 12 shows an example of a conventional standard optical fiber array. In this figure, an optical fiber array comprises a lower substrate 1 including V-shaped groove in its surface, a fiber presser substrate 3 located over the V-shaped grooves in the lower substrate 1 to press non-covered (bare) optical fibers 2 in the V-shaped grooves, and a covered fiber housing substrate 5 that presses covered optical fibers 4. Covered optical fibers 4 are inserted through a covered housing groove 6 formed in the covered fiber housing substrate 5 so that bare optical fibers 2 are aligned in the V-shaped grooves, thereby constituting the optical fiber array 7.
The optical fiber array is configured as described above, and a normal method for aligning and fixing the optical fibers 2 to the lower substrate 1 is to place cores of the bare optical fibers 2 in the V-shaped grooves from above, to place the fiber presser substrate 3 thereon, and to use an adhesive to fix the fibers. In this case, as shown in FIG. 13, when the optical fibers 2 are placed in the V-shaped grooves 8, they may collide against the tip edges 10 of protruding portions 9 formed between the plurality of V-shaped grooves 8 and may be damaged or cut, resulting in an open circuit. In addition, the tip edges 10 of the protruding portions 9 in the lower substrate may also be cut to cause an open circuit or an insufficient fiber arrangement accuracy.
In addition, if, for example, the optical fiber array is used for a fiber core selection apparatus, the fibers may be moved among the plurality of V-shaped grooves in the lower substrate.
When the fibers are moved among the V-shaped grooves in this manner, similarly as the above description the fibers 2 may be damaged or cut or the tip edges 10 in itself of the protruding portions 9 each formed between the V-shaped grooves 8 may be cut to cause an open circuit or an insufficient fiber arrangement accuracy.